When I worked in a computer store we got a batch of paper shredders and sold them all pretty fast. One customer bought one along with a custom-built computer. He was a smart fellow, as he knew just what he wanted and even asked for the installation disks to be included in case something went wrong.
Happy to oblige, we gave him all the disks. The next day, he complained that we didn’t give him the driver disk for the shredder.
The shredder, under no circumstances, required any connection to the computer. There was just a power switch. I explained it to him, and he shrugged it off when he realized his mistake and left. After that, I went into the back room and laughed till it hurt.